DE69924677T2 - Toner, image forming process, and apparatus component - Google Patents

Description

BACKGROUND THE INVENTION

Territory of invention

The The invention relates to a toner used in recording processes on which the electrophotography, an electrostatic recording or a toner jet recording is used. More precisely The invention relates to a toner for developing electrostatic Images, an image forming process using the toner and a device unit, in copy machines, Used printers and fax machines in which a toner image in advance on an electrostatic latent image carrier element is generated and then on a transmission medium to generate an image becomes.

related State of the art

In Toners used in electrophotography, in electrostatic recording and toner jet recording, it is more conventional Well known, inorganic fine particles with a small particle diameter too colored Parts (toner particles) for the purpose of controlling the chargeability, the flowability of the toner, etc. to give a good development performance, Cleaning performance and transmission performance to achieve.

however has been with toners to which such inorganic fine particles with small particle diameter, confirms that the for longer Toner used to enter a state in which the inorganic Particles with a small particle diameter are buried in the toner particle surfaces are, e.g. due to the stress exerted by the carrier particles when used as a two-component developer, due to the by the Developer coating blade and the developer feed roller imposed strain when used as a one-component developer, and due to the shocks of the toner particles against the inner walls the developer assembly and the stirring blades and between the Toner particles.

Around such inorganic fine particles having a small particle diameter digging into the toner particles less effectively, it is effectively inorganic Fine particles with a big one Use particle diameter in combination, as disclosed in the Japanese Patent Application No. 4-204751, No. 5-346682, No. 6-313980, No. 6-332235 and No. 7-92724 is disclosed.

The Addition of inorganic fine particles having a large particle diameter leads to an effect called spacer effect, wherein the surfaces of the Toner particles to which the organic fine particles with small Particle diameter adhered to a direct contacting with the carrier, with the developer coating blade, the developer supply roller, the inner walls the development assembly and the other toner particles prevented can be to reduce the stress. This leads to, that the inorganic fine particles having a small particle diameter dig in less and allow Achieving a longer one Lifetime of the toner.

Around To make this spacer effect permanent, it is preferred to use silica to use as the inorganic fine particles having a large particle diameter. The reason for this is the following: The inorganic fine particles having a large particle diameter have a weaker one electrostatic attraction to the surfaces of the toner particles as the inorganic fine particles having a small particle diameter. Therefore, the inorganic fine particles having a large particle diameter become easier from the surfaces the toner particles are released to be a result of consumption during the Development smaller in volume so that the spacer effect does not last long. Here can be the silica, which has a large amount of charge among the inorganic Fine particles and also stuck to the surfaces of the toner particles is bound, less of it can be released and can the spacer effect make it more permanent.

however can Toners to which the inorganic fine particles having a small particle diameter and Silica with a big one Particle diameter were added externally, too high a loadability in a low humidity environment, that is, they tilt to a charge, and in some ways reduced one environmental stability to have.

Meanwhile, as disclosed in Japanese Patent Application Laid-Open No. 7-104501, there has been proposed a toner in which hydrophobic silica having a particle diameter of 15 to 20 nm, hydrophobic silica having a particle diameter of 13 nm or smaller and alumina are used as external additives. This toner can achieve excellent environmental properties in the two-component developers in which carriers are used. However, in the non-magnetic one-component developers, the 15 to 20 nm hydrophobic silica can be released from the surfaces of the toner particles, failing to achieve sufficient spacer effect performance, and the silica particles can be more rapidly buried in the surfaces of the toner particles which leads to an increase in fogging and inadequate cleaning, and thereby reduces transfer efficiency. Regarding the environmental characteristics as well, no sufficient performance can be obtained, whereby the image density decreases due to the charging and results in uneven images. This is presumably due to the fact that the mechanical loading of the loading element blade in non-magnetic one-component developers is greater than in two-component developers.

SUMMARY THE INVENTION

A The object of the present invention is to provide a toner with which the above problems are solved, and an image forming method and a device unit which make use of such a toner.

A Another object of the present invention is to provide a toner which does not increase the formation of fog and does not cause defects Cleaning leads and to a reduction of the transmission efficiency itself leads to a long-term use and also no decrease in image density and any uneven images leads, even in a low-humidity environment, as well as an image forming method and a device unit, which make use of such a toner.

In order to achieve the objects of the present invention, in a first aspect, the present invention provides a toner comprising toner particles and an external additive, wherein:
the toner particles have a weight-average particle diameter of 4 μm to 9 μm; and
the external additive (i) first, hydrophobic fine silica particles having a small particle diameter (A) and having a BET specific surface area of 100 m ² / g to 350 m ² / g and a primary particle 50% particle diameter of 5 nm to 20 nm wherein they have been treated with a silane, (ii) second, hydrophobic fine silica particles having a large particle diameter (B) and having a BET specific surface area of from 15 m ² / g to 80 m ² / g and a 50% particle diameter of Primary particles of 30 nm to 150 nm, which have been treated with a silicone oil, and (iii) fine alumina particles (C) having a BET specific surface area of 50 m ² / g to 150 m ² / g.

In a second aspect, the present invention also provides an image forming method comprising:
a step of generating an electrostatic latent image to form an electrostatic latent image on a latent image bearing member; and
a development step of developing the electrostatic latent image formed on the latent image bearing member with a toner;
in which:
in the development step, the toner is supplied onto a developer carrying member by means of a developer supply roller brought into contact with the developer carrying member, the toner layer thickness is regulated by means of a developer layer thickness regulating member coming into contact with the surface of the developer carrying member, and the electrostatic latent image is developed with the toner of a layer thickness-regulated toner layer supported on the developer-carrying member;
characterized in that the toner is a toner according to the first aspect of the present invention.

A third aspect of the present invention relates to the use of a toner according to the first aspect of the invention in an apparatus unit detachably attachable to the main assembly of an image forming apparatus; the unit comprising the following:
a developer container for holding the toner; and
a developer-carrying member for supporting the toner thereon, which is held in the developer container, and for transporting the toner to a development zone.

In a fourth aspect, the present invention further provides an apparatus unit detachably mountable to the main assembly of an image forming apparatus; the unit being the following in combination includes:
a toner according to the first aspect of the invention;
a developer container for holding the toner; and
a developer-carrying member for supporting the toner thereon, which is held in the developer container, and for transporting the toner to a developer zone.

SUMMARY THE DRAWINGS

1 Figure 4 illustrates a developer assembly employed in a non-magnetic one-component development utilizing the toner of the present invention.

2 Fig. 10 is a block diagram of an example in which an image forming apparatus employing the image forming method of the present invention is applied to a printer of a facsimile system.

3 Fig. 10 illustrates an apparatus for measuring the amount of triboelectricity of the external fine particle additives used in the present invention.

4 Fig. 10 illustrates an image forming apparatus which can perform the image forming method which makes use of the toner of the present invention.

DESCRIPTION THE PREFERRED EMBODIMENTS

When Result of intensive studies by the inventors of the present Invention have been carried out was found to be through the use of two types of hydrophobic Silica fine particles with specific BET specific surface areas and special 50% particle diameter of the primary particles, the special Treatment and fine alumina particles images are obtained with a specific BET specific surface can, without causing any increase in fogging and a flawed one Cleaning and a reduction in transfer efficiency, and even with a long application, and also without one Reduction of the image density and without any uneven images respectively, even in a low humidity environment.

The Two types of hydrophobic silica fine particles are described herein grouped as particles (A) and (B), that is, hydrophobic silica fine particles with a small particle diameter (A) and hydrophobic fine silica particles with a big one Particle diameter (B). The fine alumina particles become used as particle (C).

As the hydrophobic silica fine particles having a small particle diameter (A), hydrophobic fine silica particles having a BET specific surface area of 100 to 350 m ² / g, and preferably 150 to 300 m ² / g, which have been surface-treated with a silane and the have a 50% particle diameter of the primary particles of 5 nm to 20 nm used.

The Use of such particles as an external additive of the toner allows the control of the charge property and flowability the toner to give the toner good development performance, cleaning performance and transmission power to rent.

When the small particle diameter hydrophobic fine silica particles (A) have a BET specific surface area of greater than 350 m ² / g or have a primary particle 50% particle diameter smaller than 5 nm, the particles may be in the microscopic unevenness of the toner particle surface be buried to undesirably allow insufficient control of the charging property and flowability.

When the hydrophobic fine silica particles having a small particle diameter (A) have a BET specific surface area of less than 100 m ² / g or a primary particle 50% particle diameter greater than 20 nm, the particles may not be undesirable in the toner adequate flowability provided.

The Silane for the treatment of surfaces hydrophobic silica fine particles having a small particle diameter (A) may preferably be an alkoxysilane, a silazane or a chlorosilane and more preferably a disilazane. The treatment with a Silane coupling agent, a titanium coupling agent or a silicone oil is not preferred because it does not have the toner with a sufficient flowability can provide.

The Treatment with the silicone oil may preferably be in an amount of 5 to 25 parts by weight, and more preferably from 8 to 20 parts by weight, based on 100 parts by weight of the fine Silicon oxide particles performed become. In this treatment can the hydrophobic silica fine particles having a small particle diameter (A) preferably have a water wettability of 70% or more. When the fine silica particles (A) have water wettability below 70%, can not have a sufficient amount of charge in one Environment to be achieved with high humidity.

As the hydrophobic silica fine particles having large particle diameter (B), which are an additional external additive, hydrophobic silica fine particles having a BET specific surface area of 15 to 80 m ² / g, and preferably 20 to 60 m ² / g, with a used with a silicone oil treated surface, wherein they have a 50% particle diameter of the primary particle of 30 nm to 150 nm.

When the hydrophobic silica fine particles having a large particle diameter (B) have a BET specific surface area greater than 80 m ² / g or a primary particle 50% particle diameter smaller than 30 nm, undesirably, the addition of the hydrophobic fine silica particles may expected with large particle diameter (B) spacer effect can not be observed. When the hydrophobic silica fine particles having large particle diameter (B) have a BET specific surface area smaller than 15 m ² / g or have a primary particle 50% particle diameter larger than 150 nm, undesirably many particles are released from the surfaces of the toner particles become.

In The present invention requires silica as the hydrophobic fine silica particles of large particle diameter (B) be used. The use of other inorganic fine particles except Silica, e.g., titanium oxide, alumina, tin oxide, zinc oxide, Magnesium oxide or strontium titanate is not preferred because many Particles of it from the surfaces the toner particles can be released.

The hydrophobic silica fine particles having a large particle diameter (B), the invention used are, are with a silicone oil surface treated Service. This may be the release of the hydrophobic fine silica particles with big Prevent particle diameter (B) from the surfaces of the toner particles. Treatment with anything other than the silicone oil (e.g., with an alkoxy silane, a silazane or a coupling agent) is not preferred since many hydrophobic silica fine particles having a large particle diameter (B) from the surfaces the toner particles can be released.

When the silicone oil for surface treatment the hydrophobic silica fine particles having a large particle diameter (B) can dimethyl silicone, methylphenyl or methyl hydrogen silicone oil (Methyl hydrogen silicone oil) be used. In particular, dimethylsilicone oil is preferred. The silicone oil may preferably have a viscosity at 25 ° C of 100 cSt or less.

The Treatment with the silicone oil may preferably be in an amount of 2 to 20 parts by weight, and more preferably from 5 to 15 parts by weight, based on 100 parts by weight of the fine Silica particles become. In this treatment can the hydrophobic silica fine particles having a large particle diameter (B) preferably have a water wettability of 80% or more. When the fine silica particles (B) have water wettability below 80% such particles have a weak adhesion to the surfaces of the Have toner particles in a high humidity environment, wherein they are easily released from it.

The hydrophobic silica fine particles having a small particle diameter (A) can preferably to the toner in an amount of (a) from 0.3 to 2.5 parts by weight and more preferably from 0.5 to 2.0 parts by weight based on 100 parts by weight of the toner particles are added. The addition hydrophobic silica fine particles having a small particle diameter (A) in an amount (a) of less than 0.3 parts by weight, the Achieving adequate fluidity and complicate their Addition in an amount (a) greater than 2.5 parts by weight may result in an excess lead to silica, which is not complete to the surfaces of the toner particles, which easily causes film formation the photosensitive element and to a pressure chamber contamination leads.

The hydrophobic silica fine particles having a large particle diameter (B) may preferably be based on the toner in an amount (b) of 0.05 to 1.5 parts by weight, more preferably 0.1 to 1.0 part by weight to 100 parts by weight of the toner particles. The addition of the hydrophobic fine Silica particles having a large particle diameter (B) in an amount (b) of less than 0.05 part by weight can not provide a sufficient spacer effect, and their addition in an amount (b) of more than 1.5 parts by weight may become one Excess silica lead, which does not completely adhere to the surfaces of the toner particles, which easily leads to film formation in the photosensitive member and to a pressure chamber contamination.

As described above the hydrophobic silica fine particles having a large particle diameter (B) by selecting their BET specific surface area and surface treatment prevented from releasing from the surfaces of the toner particles become. here we can the hydrophobic silica fine particles having a large particle diameter (B) a quantity of triboelectricity from -60 up to -100 mC / kg have. The particles with a similar BET specific surface area, but where no use made of the silicone oil as a treatment agent was, have a Triboelektrizitätsmenge of about -30 to -50 mC / kg. It is believed that a higher Absolute value of the quantity of triboelectricity can effectively prevent the particles (B) from coming off the surfaces of the particles Toner particles are released.

If the hydrophobic silica fine particles having a large particle diameter (B) a quantity of triboelectricity less than -60 have mC / kg as an absolute value in the minus range, the hydrophobic silica fine particles of large particle diameter (B) easy from the surfaces the toner particles released. When the hydrophobic fine silica particles with big Particle diameter (B) has a quantity of triboelectricity greater than -100 mC / kg as an absolute value in the minus range, can they agglomerate each other electrostatically to form a uniform adhesion the toner particles to the surfaces to complicate.

The hydrophobic silica fine particles having a small particle diameter (A) can preferably a quantity of triboelectricity from -40 to -150 mC / kg.

If the hydrophobic silica fine particles having a small particle diameter (A) a quantity of triboelectricity less than -40 have mC / kg as an absolute value in the minus range, the hydrophobic silica fine particles having a small particle diameter (A) slightly off the surfaces the toner particles under mechanical stress of the toner particles be released. When the hydrophobic fine silica particles with small particle diameter (A), a quantity of triboelectricity greater than -150 mC / kg as an absolute value in the minus range, the lead Toner particles in a low humidity environment easily to a charge.

In the present invention, as another external additive, in addition to the above two types of fine silica particles, fine alumina particles having a BET specific surface area of 50 to 150 m ² / g are used as the fine alumina particles (C). This can prevent the toner from causing charging particularly in a low-humidity environment.

When the fine alumina particles (C) have a BET specific surface area smaller than 50 m ² / g, the fine alumina particles (C) can be released from the surfaces of the toner particles to selectively participate in development, resulting in a smaller amount present so as to cause a lowering of the image density or to cause uneven images ascribable to charge-up (charging) of the toner in a low-humidity environment. When the fine alumina particles (C) have a BET specific surface area larger than 150 m ² / g, the fine alumina particles (C) may cover the hydrophobic silica fine particles having large particle diameter (B) to undesirably adhere the latter to the surface To block surfaces of the toner particles.

The Fine alumina particles (C) may preferably have a quantity of triboelectricity from -30 to +20 mC / g and more preferably from -10 to +10 mC / g. This is for the prevention of the charging of the toner effectively.

If the fine alumina particles (C) have a quantity of triboelectricity greater than -30 mC / g having an absolute value in the minus range can be difficult its charging the toner in a low humidity environment to prevent. If they have a quantity of triboelectricity greater than +20 mC / g as an absolute value in plus range, you can electrostatically with the hydrophobic fine silica particles with small particle diameter (A) and hydrophobic fine silica particles with big Agglomerate particle diameter (B).

The Fine alumina particles (C) may preferably be in the toner in an amount of 0.01 to 2.0 parts by weight, and more preferably from 0.03 to 1.5 parts by weight, based on 100 parts by weight of Toner particles are added.

If the fine alumina particles (C) in an amount of less than 0.01 part by weight, it is difficult to prevent that the toner is charged in a low humidity environment becomes. When added in an amount of greater than 2.0 parts by weight can be, the toner is not sufficient amount of charge in one Environment with high humidity, making it easy to a fog tends.

In the present invention, the small particle diameter hydrophobic fine silica particles (A), the large particle diameter hydrophobic fine silica particles (B), and the fine alumina particles (C) used as external additives may preferably be used in an amount of (a), Amount (b) or an amount (c) are added in the ratio that they satisfy the following relationships:
a: b: c = 1: 0.10 to 0.65: 0.05 to 0.50
and further preferably satisfy the following relationship:
a: b: c = 1: 0.15 to 0.45: 0.05 to 0.40.

If the hydrophobic silica fine particles having a large particle diameter (B) are added in an amount (b) of less than 0.10, the spacer effect can be so insufficient be that he has a reduction in image density and fogging as a result of the use caused. If they are in a crowd (b) are added of more than 0.65, the toner may have a low flowability have, which easily leads to uneven image density.

If the fine alumina particles (C) in an amount (c) of less When 0.05 is added, the charging of the toner easily occurs in a low-humidity environment, which is easy to one Reduction of image quality and leads to fogging. If they are added in an amount (c) greater than 0.5, can the amount of charge of the toner in a high humidity environment be lower, which easily leads to a strong veil.

The Addition of the fine alumina particles (C) brings excellent Performance in a low-humidity environment, such as confirmed above has been. To make the performance less of the environment of high humidity can deviate the fine alumina particles (C) more preferably a water wettability of not more than 30%. The use of the fine alumina particles (C) with a water wettability of not more than 30% allows the Prevent toner from charging in a low-light environment Moisture by adding it in a small amount and at the same time allows he prevents the lowering of the charge power of the toner in a high humidity environment, so that the sinking of the picture quality or fogging can be prevented.

Fine Aluminum oxide particles (C) with a water wettability of more than 30% can preferably to the toner in an amount (c1) of 0.05 to 2.0 parts by weight and more preferably from 0.07 to 1.5 parts by weight based on 100 parts by weight of the toner particles are added. On the other hand the fine alumina particles (C) having a water wettability can be used by not more than 30%, the charges of the toner accordingly designed to be licking by its addition in a small amount be, and therefore can it prefers to the toner in an amount (c2) of 0.01 to 1.0 Parts by weight, and more preferably from 0.03 to 0.7 parts by weight, based to 100 parts by weight of the toner particles.

Accordingly, with respect to the above ratio, the amount (a), the amount (b) and the amount (c) of the small particle diameter hydrophobic fine silica particles (A), the large particle diameter hydrophobic fine silica particles (B) and the fine aluminum oxide particles (C) are different. their preferable ratio between the amount (c1) and the amount (c2) when the fine alumina particles (C) have a water wettability of more than 30% and when the fine alumina particles (C) have a water wettability of not more than 30%. As particularly mentioned, the ratio may preferably satisfy the following relationship when the fine alumina particles (C) have a water wettability of more than 30%:
a: b: c1 = 1: 0.10 to 0.65: 0.20 to 0.50
and further preferably satisfy the following relationship:
a: b: c1 = 1: 0.15 to 0.45: 0.30 to 0.40.

When the fine alumina particles (C) have a water wettability of not more than 30%, the ratio may preferably satisfy the following relationship:
a: b: c2 = 1: 0.10 to 0.65: 0.05 to 0.35
and further preferably satisfy the following relationship:
a: b: c2 = 1: 0.15 to 0.45: 0.05 to 0.25.

In In the present invention, the BET specific surface area of the fine particles by adsorption of nitrogen gas on the sample surfaces below Use of a special surface measuring device AUTOSOBE 1 (manufactured by Yuasa Ionics Co.) and the specific one surface is calculated by the BET multi-point method.

In In the present invention, the 50% particle diameter of primary of the fine silica particles using a transmission electron microscope measured. A photograph is taken at 150,000x magnification and the photograph is enlarged four more times to the particle diameter the primary particle to eat. This is measured at 100 samples and a 50% value The measurements are taken as the 50% particle diameter of the primary particles considered.

In In the present invention, the amount of triboelectricity becomes the fine particle of the external additive in the following manner and Measured way.

A Mixture of the fine particles of the external additive and a carrier is in a bottle made of polyethylene with a volume of 50 ml and manually for about 5 minutes shaken. Here is called the carrier a silicone-coated ferrite carrier (a product produced by 400 mesh passes) and the fine particles of the external Additive and the carrier be in a weight ratio mixed by 2:98.

Next, as in 3 is shown, the mixture in an amount Wo (g: about 0.5 to 1.5 g) in a measuring container made on the bottom of metal 32 given on which a sieve 33 is provided with 500 mesh, and the container is made with a plate made of a metal 34 covered. The total weight of the measuring container 32 at this time is weighed and expressed as W ₁ (g). Next is in a suction device 31 (Of an insulating material at least on the part in contact with the measuring container 32 comes, manufactured), air from a suction opening 37 sucked and an airflow control valve 36 is used to control the pressure by means of a vacuum indicator 35 is displayed, operated at 2,450 hPa. In this state, the suction is performed well, preferably for 2 minutes, to remove the fine particles of the external additive by suction.

V (Volt):

durch ein Potenziometer 39 angezeigtes Potenzial;

C (μF):

Kapazität eines Kondensators 38;

W₂ (g):

Gewicht des Messbehälters nach dem Absaugen; und

T:

Teilchen/Träger-Verhältnis.

The quantity of triboelectricity Q of the external particles of the external additive in this aspiration, corrected to 100%, is defined as follows:

V (volts):

through a potentiometer 39 indicated potential;

C (μF):

Capacity of a capacitor 38 ;

W ₂ (g):

Weight of the measuring container after aspiration; and

T:

Particles / carrier ratio.

In The present invention provides the water wettability of the fine particles measured in the following manner.

In A 200 ml separatory funnel is charged with 1.0 g of a sample and 100 ml of ion-exchanged water are added thereto. The separating funnel is placed in a tumbling shaker (manufactured by Shinmaru Enterprises Co.) to disperse at 90 rpm for 10 minutes used. The separating funnel is taken out and for 10 minutes ditched. Thereafter, a 20 to 30 ml portion is removed and in a 10 mm cell of a spectrophotometer UV-210 (manufactured from Shimadzu Corporation). Using ion-exchanged Water as a reference is the cloudiness the water layer measured at a wavelength of 500 nm and the value determined in this measurement is called water wettability considered.

In of the present invention the toner particles preferably have a weight-average particle diameter from 4 to 9 μm exhibit. When the toner particles have a weight average particle diameter smaller than 4 μm may have uneven pictures or fogging may occur due to the non-uniform charge. If they have a weight-average particle diameter greater than 9 μm, can Toner dots around the fine line images unwanted Way amplified occur.

In The present invention will be the weight average particle diameter of the toner with a Coulter counter, Model TA-II (manufactured by Coulter Electronics, Inc.). An interface (made by Nikkaki K.K.) that has a number distribution and outputs a volume distribution and a personal computer PC9801 (manufactured by NEC.) are connected. As an electrolytic solution becomes an aqueous 1% NaCl solution manufactured using sodium chloride of the highest purity class. For example, ISOTON R-II (trademark, manufactured by Coulter Scientific Japan Co.). The measurement is made by adding 0.1 to 5 ml of a surface-active By means of a dispersing agent, preferably an alkyl benzene sulphonate, to 100 to 150 ml of the above aqueous electrolytic solution and by further addition of 2 to 20 mg of a sample to be measured. The electrolytic solution, in which the sample had been suspended is allowed to stand for about 1 minute until about 3 minutes dispersed in an ultrasonic disperser. The volume distribution and the number distribution are determined by measuring the volume and the Number of toner particles with diameters of 2 μm or larger by the above Coulter counter, model TA-II calculated using an aperture (aperture) of 100 μm as an aperture. Then is considered as inventive value the weight-based weight average determined from the volume distribution Particle diameter (D4) (the average of each channel becomes as the representative Value for everyone Channel used) determined.

When channels become 13 channels used, which is from 2.00 to less than 2.52 microns, of 2.52 to less than 3.17 μm, from 3.17 to less than 4.00 μm, from 4.00 to less than 5.04 μm, from 5.04 to less than 6.35 microns, from 6.35 to less than 8.00 microns, from 8.00 to less than 10.08 microns, from 10.08 to less than 12.70 μm, from 12.70 to less than 16.00 μm, from 16.00 to less than 20.20 μm, from 20.20 to less than 25.40 μm, from 25.40 to less than 32.00 microns and from 32.00 to less than 40.30 μm.

In In the present invention, the toner may preferably have an average circularity from 0.950 to 1.000, more preferably from 0.950 to 0.990 and still more preferably from 0.960 to 0.985, when using a flow particle image analyzer is measured. If the Toner a medium circularity of less than 0.950, it tends to be due to the non-uniform charge to uneven pictures and a haze. If he has a medium circularity of more than 0.990, it tends to reduce the cleaning performance.

The circularity referred to in the present invention is used as a simple method for quantitative expression of the shape of the toner. In the present invention, it is measured by a flow particle image analyzer FPIA-1000 manufactured by Toa Iyou Denshi KK, and the circularity of the measured particles is calculated according to the expression shown below, and the sum total of the circularity of all the measured particles is determined by the total number of particles divided and the value obtained is defined as the mean circularity.

The medium circularity is made with the flow particle image analyzer FPIA-1000 by Toa Iyou Denshi K.K., measured. The toner whose mean circularity is measured is weighed in an amount of about 0.02 g and will be uniform in ion-exchanged water with a surfactant in one small amount (about 10 ml, 20 ° C) dispersed. As a dispersing agent, an ultrasonic dispersing machine UH-50 manufactured by SMT Co., used (a tip with 5 mm diameter from a Titanium alloy is used as a vibrator), and the dispersion time will be 5 minutes or longer adjusted, the dispersion being suitably cooled in this way, the dispersing medium temperature does not exceed 40 ° C. Under use of the flow particle image analyzer become at least 1,000 particles with one of the circularity corresponding diameter of 0.66 microns to 159.21 microns for measurement selected from their average circularity.

The sum of the measurements is described in a catalog of FPIA-1000 published by Toa Iyoudenshi KK (1995, June edition) in a manual of the meter and in Japanese Patent Application Laid-Open No. 8-136439, and is as follows:
The sample dispersion is allowed to flow through channels (extending along the flow direction) of a flat transparent flow cell (thickness: approximately 200 μm). A stroboscope and charge coupled device (CCD) camera are solidified with respect to the flow cell at opposite positions so as to form a light path that transversely extends with respect to the thickness of the flow cell. During the flow of the sample dispersion, the dispersion is irradiated with stroboscopic light at intervals of 1/30 second to obtain an image of the particles flowing through the cell, so that a photograph of each particle as a two-dimensional image in a particular, parallel to the Flow cell lying area is recorded. From the area of the two-dimensional image of each particle, the diameter of a circle having the same area as the diameter corresponding to the circle is calculated.

The circularity of each particle is calculated from the projected area of the two-dimensional image of each particle and the perimeter length of a projected image using the above formula for Calculation of circularity calculated.

The Measuring device FPIA-1000, which was used according to the invention used a calculation method in which the circularity of a each particle is calculated, then in a calculation of the mean circularity the obtained particles having the circularity of 0.4 to 1.0 divided into 61 Classes are classified, and the average circularity through Use of the center of the divided points and a frequency is calculated. However, the differences between the middle Circularity, the calculated by this calculation method, and mean circularity calculated by using the calculation formula in which the circularity the particle is used directly as mentioned above, much smaller and can essentially neglected become. In the present invention, the calculation formula, in which the circularity the particle is used directly, due to the handling of the Data such as shortening the calculation times and the simplification of the calculation formula used, but this partially modified calculation method can be used in the invention.

It are no special restrictions like the toner particles used in the present invention are to produce. To the toner with the average circularity of 0.950 or more, and preferably from 0.95 to 0.990, the Toner particles preferably by suspension polymerization, mechanical Pulverization or a spherical Treatment to be made. In particular, the suspension polymerization prefers.

One Process for producing the toner particles by suspension polymerization will be described below.

When The first becomes a polymerizable monomer composition that is polymerizable Monomers and added substance with low softening point polar resins, colorants, Charge control agents, polymerization initiators and other additives, the uniformly dissolved by means of a homogenizer or an ultrasonic disperser or have been dispersed in an aqueous phase with a dispersion stabilizer, by means of a mixing machine, such as an ordinary stirrer, homomixer or homogenizer dispersed. Here is a granulation during the control of the stirring speed and time performed, such that those generated from the polymerizable monomer composition Drop the desired one Have toner particle size can. After granulation can be stirring be carried out to such an extent that the state of the particles by the action of the dispersion stabilizer is maintained and the particles are prevented from settling can. The polymerization may be at a polymerization temperature setting at 40 ° C or above and preferably from 50 to 90 ° C carried out become. In the last half The temperature of the polymerization can be increased and also can the watery Medium partially from the reaction system in the second half of the Reaction or removed after the reaction is complete, not to reacted polymerizable monomers and by-products, which at the time of developmental fixation can cause odors, too remove. After completion of the reaction, the generated toner particles become collected by washing and filtration, followed by drying. In such a suspension polymerization, more ordinary Water is preferred as the dispersion medium in an amount from 300 to 3,000 parts by weight, based on 100 parts by weight of the polymerizable monomer composition, be used.

The particle size distribution and the particle diameter of the toner particles can be controlled by a method in which the type or amount of a poorly water-soluble inorganic salt or a dispersant that effects a protective one Colloids has varied; or a method in which the mechanical device conditions, e.g. the stirring conditions such as the peripheral speed a rotor, the residence times and the shape of the stirring blades and the shape of a reaction vessel, or the concentration of the solid in the aqueous Medium can be varied, and thus the inventively used desired Toner particles are obtained.

The used according to the invention polymerizable monomer may include styrenic monomers such as styrene, o-, m- or p-methylstyrene and m- or p-ethylstyrene; Acrylic or methacrylic ester monomers, such as methyl acrylate or methacrylate, propyl acrylate or methacrylate, Butyl acrylate or methacrylate, octyl acrylate or methacrylate, Dodecyl acrylate or methacrylate, stearyl acrylate or methacrylate, Behenyl acrylate or methacrylate, 2-ethylhexyl acrylate or methacrylate, Dimethylaminoethyl acrylate or methacrylate and diethylaminoethyl acrylate or methacrylate; and olefin monomers, such as butadiene, isoprene, Cyclohexene, acrylic or methacrylonitrile and acrylic acid amide include, each of which is preferably used.

When are the polar resin added at the time of the polymerization Styrene / acrylic or methacrylic acid copolymers, Maleic acid copolymers, Polyester copolymers and epoxy copolymers preferably used.

The Substance with a low softening point used according to the invention may be a paraffin wax, a polyolefin wax, a Fischer-Tropsch wax, Amide waxes, higher fatty acids, Ester waxes and derivatives of these or graft or block compounds of these.

When that in the toner particles according to the invention used colorants become soot (carbon black) and yellow, magenta and cyan dyes toned in black dye, shown below, used as black colorants.

When the yellow colorant compounds are used which are formed by condensation azo compounds, Isoindolinone compounds, anthraquinone compounds, azo metal complexes, Methine compounds or Allylamidverbindungen are classified. In particular, C.I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168 and 180 are preferred used.

When the magenta colorant become condensation azo compounds, Diketopyrrolopyyrolene compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazole compounds, Thioindigoverbindungen or perylene compounds used. Especially are C.I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221 and 254 particularly preferred.

When the cyan colorant can Copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds or basic dye lake compounds. Especially C.I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62 and 66 particularly are preferably used.

each this colorant can be in a lot of about 1 to 20 parts by weight, based on 100 parts by weight of the polymerizable Monomers, are added. If a magnetic material than the black dye It can be used unlike the other colorants in an amount of about 40 to 150 parts by weight, based on 100 parts by weight of the polymerizable Monomers, are added.

When used according to the invention Charge control can known means are used. Charge control agents that neither a polymerization inhibiting effect still remain in the aqueous Dissolve dispersion medium, are particularly preferred. As special compounds are considered negative Charge control agent Metal compounds of salicylic acid, naphthoic acid, dicarboxylic acid and Derivatives thereof, polymeric compounds with sulfonic acid or carboxylic acid in the side chain, boron compounds, urea compounds, silicon compounds and Carycsaren can be used. As a positive charge control agent are preferably quaternary Ammonium salts, polymer-type compounds with such a quaternary ammonium salt in the side chain, guanidine compounds and imidazole compounds used. The charge control agent may preferably be in one Amount of 0.5 to 10 parts by weight based on 100 parts by weight of the polymerizable monomer.

Of the Polymerization initiator used in the invention may be e.g. Azo-type polymerization initiators such as 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile) 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile; and peroxide type polymerization initiators, such as benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, Cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide and lauroyl peroxide include.

Of the Polymerization initiator can usually be used in an amount from 0.5 to 20% by weight, based on the weight of the monomers which are dependent of the invention intended Degree of polymerization varies. The polymerization initiator can dependent on of the procedure for the type of polymerization varies somewhat and can be alone or in the form of a mixture, being based on his 10 hour half life temperature.

The Dispersants used in the suspension polymerization can e.g. as inorganic oxide compounds tricalcium phosphate, Magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, Magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, Calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, Include alumina, magnetic materials and ferrite. When organic compounds may e.g. Polyvinyl alcohol, gelatin, Methylcellulose, methylhydroxypropylcellulose, ethylcellulose, carboxymethylcellulose sodium salt and strength include, which in the aqueous Phase dispersed in their use.

Everyone These stabilizers may preferably be in an amount of from 0.2 to 2.0 parts by weight, based on 100 parts by weight of the polymerizable Monomers, are used.

When these dispersants can commercially available, be used as they are. However, dispersed particles with a fine and uniform Get particle size, can the fine particles of the inorganic compound in the dispersion medium be generated under a high speed stirring. For example in the case of tricalcium phosphate, an aqueous sodium phosphate solution and a aqueous Calcium chloride solution be mixed under a high speed stirring to one Fine particle dispersant preferred for the suspension polymerization to obtain.

Around To make these dispersants finer, 0.001 to 0.1 parts by weight a surface active To be used in combination. In particular, they can be commercial available, nonionic, anionic or cationic surfactants Funds are used. For example, those used are preferred Sodium dodecylsulfate, sodium tetradecylsulfate, sodium pentadecylsulfate, Sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate and Calcium oleate.

One Process for producing the toner particles by pulverization (Powdered toner particles) will be described below.

The powdered toner particles are prepared using a binder, a coloring agent, a charge control agent and other additives.

The Binder resin used in the pulverized toner particles in the The present invention may include the following: polystyrene, Poly-α-methylstyrene, Styrene / propylene copolymer, styrene / butadiene copolymer, styrene / vinyl chloride copolymer, Styrene / vinyl acetate copolymer, styrene / acrylate copolymer, styrene / methacrylate copolymer, Vinyl chloride resins, polyester resins, epoxy resins, phenolic resins and Polyurethane resins, each of which is alone or in the form a mixture can be used. Especially preferred are Styrene / acrylate copolymer, Styrene / methacrylate copolymer and polyester resins.

When the invention used dye can all known colorants be used, including e.g. the following: carbon black (carbon Black); oil-soluble dyes, such as C.I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207, 209, C.I. Pigment Violet 19, C.I. Vat Red 1, 2, 10, 13, 15, 23, 29, 35, C.I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121, C.I. Disperse Red 9, C.I. Solvent Violet 8, 13, 14, 21, 27, and C.I. Disperse Violet 1; basic dyes, such as C.I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40 and C.I. Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28; C.I. Pigment Blue 2, 3, 15, 16, 17; C.I. Vat Blue 6; C.I. Acid Blue 45; C.I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 83; and C.I. Vat Yellow 1, 3, 20; each of them alone or in the form of a mixture can be used.

The dye may be used in an amount of from 0.1 to 60 parts by weight, and preferably from 0.5 to 50 parts by weight, based on 100 parts by weight of the binder resin used become.

positive Charge control agents added when the toner particles used in the invention can be adjusted so that they are positively chargeable, the include: Nigrosine dyes; with fatty acid metal salts modified products, quaternary Ammonium salts such as tributylbenzylammonium 1-hydroxy-4-naphthosulfonate and Tetrabutylammonium tetrafluoroborate and analogs of these, including Onium salts, such as phosphonium salts, and lake pigments of these; Triphenylmethane dyes and lake pigments of these (Lakebildungsmittel can Tungstophosphoric acid molybdophosphoric, Wolframmolybdophosphorsäure, tannic acid, Lauric acid, Gallic acid, Ferricyanide and ferrocyanide); Amine and polyamine compounds; Metal salts of higher fatty acids; acetylacetone; Diorganotin oxides, such as dibutyltin oxide, Dioctyltin oxide and dicyclohexyltin oxide; and diorganotin borates, such as dibutyltin borate, dioctyltin borate and dicyclohexyltin borate.

When negative charge control agents added if the invention used Toner particles are controlled so that they are negatively chargeable are organic metal complexes or chelate compounds are effective, which in particular monoazometal complexes, acetylacetone metal complexes, Metal complexes of the aromatic hydroxycarboxylic acid type or of the aromatic Dicarboxylic acid type, aromatic hydroxy, aromatic mono- or polycarboxylic acids and metal salts thereof, Anhydrides thereof or esters thereof, and phenol derivatives thereof such as Bisphenol effective.

each The charge control agent may be used in an amount of 0.1 to 15 parts by weight and preferably from 0.5 to 10 parts by weight, based on 100 parts by weight of the binder resin.

One Release agent may optionally be added to the powdered toner particles be added in the present invention. It can e.g. include the following: aliphatic hydrocarbon waxes or oxides thereof, such as low molecular weight polyethylene, low molecular weight Polypropylene, paraffin wax and Fischer-Tropsh wax; Waxes, which are mainly made Fettsäureestern are built up, such as carnauba wax and montan acid ester wax, or those obtained by deoxidation treatment of a part or the Whole of it will be obtained; saturated, straight-chain fatty acids, such as about palmitic acid, stearic acid and montanic acid; unsaturated fatty acids, such as brandy, eleostearic and parinaric acid; saturated Alcohols, such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, Carnaubyl alcohol, ceryl alcohol and melissyl alcohol; polyvalent Alcohols, such as sorbitol; Fatty acid amides, such as linoleic acid amide; saturated fatty acid bisamides such as methylenebis (stearic acid amide); unsaturated fatty acid bisamides such as ethylenebis (oleineamide); aromatic bisamides, such as N, N'-distearylisophthalic acid amide; Fatty acid metal salts, such as zinc stearate; grafted waxes by grafting Vinyl monomers, such as styrene, to aliphatic hydrocarbon waxes to be obtained; partially esterified products of polyhydric alcohols with fatty acids, such as monoglyceride behenate; and methyl esterified products a hydroxyl group produced by hydrogenation of vegetable fats and oils to be obtained. The release agent may be used in an amount of 0.1 to 20 parts by weight, and preferably 0.5 to 10 parts by weight, based to 100 parts by weight of the binder resin.

When next become this binder resin, release agent, charge control agent and colorants by means of a mixing machine, such as a Henschel mixer or a ball mill mixed to make a mixture, then the mixture by means of a heat kneading machine, such as a heat roller, a kneader or an extruder melt kneaded to the resins with each other to fuse and the charge control agent and the colorant to disperse or dissolve in it, and the kneaded product is cooled to solidify, followed from a fine pulverization by means of a mechanical device, make it the desired one Having particle size, and further followed by classification to the particle size distribution to make sharp. Alternatively, a finely pulverized product, the by an impact of the cooled and solidified product against a target under a jet stream has been obtained by means of heating or a mechanical impact force spherical or curly be made.

To the toner particles obtained by the above-described methods become externally hydrophobic fine silica particles with small Particle diameter (A), hydrophobic fine silica particles with great Added particle diameter (B) and fine alumina particles (C), e.g. by a method in which the particles are used a mixer with high speed stirring, such as a Henschel mixer, are stirred at a peripheral speed of about 20 to 50 m / s, to adhere the latter particles (A) to (C) to the former.

Of the Inventive toner can be effective in any imaging process. In particular, can he most effectively in the method described below be.

It is an image forming process in which an electrostatic latent image formed on a latent image bearing member is using a one-component development assembly with a developer coating blade functioning as a developer layer thickness regulating element serves, and a developer feed roller, which serves as a developer coating member which is in contact or contact with the surface a developer carrier element be brought, developed. The toner is passed through the developer supply roller on the developer carrier element applied and then in a thin layer on the developer coating blade coated, while the toner is electrostatically charged. Any toner that did not participate in the development and on the developer-carrier element is left from the surface of the developer carrier element stripped off by the developer feed roller. This procedure allows a uniform Charging through a thin film education and therefore can produce good images with low fogging, but has the problem that the toner may be degraded earlier so a shorter one Toner lifetime due to the greater stress of the Toners compared to other development methods, e.g. one Two-component development process, accompanied. The toner according to the invention is opposite Such a load can be loaded and has a long lifetime. Therefore, he can when using in such a development process be very effective.

The above development method will be described with reference to 1 described below.

A development board 70 has a development tank 71 for holding a non-magnetic one-component developer 76 as a non-magnetic toner, a developer carrying member 72 for supporting the in the development container 71 held, non-magnetic one-component developer 76 on it and for transporting it to the development zone, a feed roller 73 for feeding the non-magnetic one-component developer to the developer-carrying member, an elastic blade 74 as a developer layer thickness regulating member for regulating the thickness of a developer layer formed on the developer carrying member, and a stirring member 75 for stirring the non-magnetic one-component developer 76 in the development tank 71 is held.

reference numeral 69 stands for a latent image-bearing member for holding an electrostatic latent image thereon, on which the electrostatic latent images are formed by an electrophotographic processor or an electrostatic recorder (not shown). The reference number 72 represents a development sleeve serving as the development support member and includes a non-magnetic sleeve formed of aluminum or stainless steel.

The developing sleeve as the development support element can be done using a raw tube made of aluminum or stainless steel, as it is, can be prepared and preferably by spraying glass beads on her to the uniform Roughening the surface, by mirroring their surface or by coating their surface prepared with a resin become. In particular, the method for coating the sleeve surface with a resin preferably be used, as it is a slight adjustment the surface roughness and lubricity the sleeve and a simple impartation of lubricity of the sleeve surface Dispersing various particles in the resin allows.

It There is no particular restriction with regard to the resin used for coating the sleeve surface and the various particles added to the resin. As the resin can preferably thermoplastic resins, such as styrene resin, vinyl resin, Polyethersulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, Fluororesin, cellulose resin and acrylic resin; and thermosetting or photocuring resins, such as epoxy resin, polyester resin, alkyd resin, phenolic resin, melamine resin, Polyurethane resin, urea resin, silicone resin and polyamide resin used become.

When the various particles added thereto are preferably particles resins, such as PMMA, acrylic resin, polybutadiene resin, polystyrene resin, Polyethylene, polypropylene, polybutadiene or a copolymer of any of these, benzoguanamine resin, phenolic resin, polyamide resin, Nylon, fluororesin, silicone resin, epoxy resin and polyester resin; Soot, like furnace black, lamp black, thermal black (inactive black), acetylene black and carbon black (channel black); Metal oxides, such as titanium oxide, tin oxide, zinc oxide, molybdenum oxide, Potassium titanate, antimony oxide and indium oxide; Metals, such as aluminum, Copper, silver and nickel; and inorganic fillers, such as graphite, Metal fibers and carbon fibers, can be used.

The non-magnetic one-component developer 76 gets into the development tank 71 held up and is on the developer carrier element 72 by means of a feed roller 73 fed. The feed roller 73 comprises a foamed material, such as polyurethane foam, and rotates at a relative velocity which is non-zero in the forward direction or reverse direction with respect to the developer carrying member, so that the developer can be supplied to the developer carrying member and also the developer stored on the developer carrying member after Transmission remains (the developer who does not participate in the development), can be removed. The on the developer carrier element 72 supplied non-magnetic one-component developer becomes uniform and in a thin film by means of the elastic blade 74 as a developer layer thickness regulating member.

For the elastic Coating blade is effective in contact with the developer carrying member a pressure of 0.3 to 25 kg / m and preferably from 0.5 to 12 kg / cm as a linear pressure in the generating direction of the developer carrying member to be brought. When the contact pressure (Contact pressure) is less than 0.3 kg / m, it is difficult to use the non-magnetic One-component developers uniformly layer what to a broad charge amount distribution of the non-magnetic one-component developer leads, resulting in a fog or black spots around the Line images leads. When the contact pressure greater than 25 kg / m is a big one Pressure exerted on the non-magnetic one-component developer, thereby a deterioration of the non-magnetic one-component developer and causing the occurrence of agglomerations of the non-magnetic one-component developer and thus such pressure is not preferred and he is also not preferred because a large torque required is to the developer carrier element drive. This means, the adaptation of the contact pressure to 0.3 to 25 kg / m an effective loss of agglomeration of the non-magnetic one-component developer and allows a rapid increase in the charge amount of non-magnetic One-component developer.

When The elastic blade are rubber-elastic materials, such as such as silicone rubber, urethane rubber and NBR, elastomers, such as such as polyethylene terephthalate and polyamide, and elastic elements Metal, such as stainless steel, steel and phosphor bronze can be used. A composite of some of these can also be used. It may preferably be one which is a metal sheet of SUS stainless steel or phosphor bronze with resilience on which a rubber material, such as urethane or silicone rubber or an elastomer of various Types, such as a polyamide elastomer, provided by injection molding is.

In this non-magnetic one-component developer and in the system in which the non-magnetic one-component developer is coated in a thin layer on the developing sleeve by means of a blade, the thickness of the one-component non-magnetic Developer can be made on the development sleeve smaller than the gap α, where the developing sleeve and the side of the latent image bearing member and an intermediate electric field can be applied to this gap. This is preferred in order to obtain a sufficient image density. More specifically, a developing bias formed from an alternating electric field or formed by superimposing a DC electric field on an alternating electric field can be formed along the developing sleeve 72 and the latent image bearing member 69 about one in 1 shown biasing means are applied. This makes it easier for the one-component nonmagnetic developer to migrate from the surface of the developing sleeve to the surface of the latent image bearing member, and thus images of much better quality can be obtained.

In of the present invention the gap α between the latent image bearing member and the developer carrying member preferably be adjusted to e.g. from 50 to 500 microns, and the layer thickness of the developer layer on the developer carrier element supported is present, e.g. from 40 to 400 μm is.

The developing sleeve rotates with a peripheral speed of 100 to 200% in relation on the latent image carrier element. The alternating electric field may preferably be peak-to-peak voltage of 0.1 kV or above, preferably from 0.2 to 3.0 kV and more preferably from 0.3 to 2.0 kV be created. The alternating bias can be at a frequency from 1.0 to 5.0 kHz, preferably from 1.0 to 3.0 kHz, and more preferably be applied from 1.5 to 3.0 kHz. As the waveform of the alternating Bias can be a square waveform, a sine waveform, a Sawtooth waveform and a triangle waveform be used. An asymmetrical AC bias with a different one Time for which Forward / reverse voltages can be created, can also be used. It is also preferable to superimpose a DC bias.

The device unit according to the invention is described with reference to 1 described.

The inventive device unit is removable to the body of the image forming apparatus (e.g., a copier, a laser beam printer or a fax machine).

In the in 1 In the embodiment shown, the device unit is the development device (assembly). 70 and the developing device is detachably mounted to the body of the image forming apparatus.

Thus, the developing device has the developer 76 , the development tank 71 , the developer-carrying element 72 , the feed roller 73 , the developer layer thickness regulating member 74 and the stirring element 75 , As the device unit of the present invention, it may at least be the developer 76 , the development tank 71 and the developer-carrying member 72 to have.

The unit may further comprise at least one element together as a unit, selected from the latent image carrier element, the cleaning element and the charge element existing group.

When the image forming method of the present invention is applied to a printer of a facsimile machine, the photo-wise exposure light L serves as an exposure light used for printing the received data. 2 illustrates an example thereof in the form of a block diagram.

A control unit 91 controls a picture reading part 90 and a printer 99 , The entire controller 91 is done by means of a CPU 97 controlled. The image data output from the image reading part is transferred to another facsimile station via a transmission circuit 93 Posted. The data received from the other station becomes a printer 99 via a receiving circuit 92 Posted. The addressed image data are stored in an image memory 96 saved. A printer controller 98 controls the printer 99 , The reference number 94 stands for a telephone.

The one of a circuit 95 received images (image information from a connected via the circuit remote terminal) are in the receiving circuit 92 demodulated and then subsequently in a frame buffer 96 stored after the image information by means of the CPU 97 has been decoded. Then, if the images for at least one page in the memory 96 have been saved, the image recording performed for this page. The CPU 97 reads the image information for a page from memory 96 and sends the encoded image information for one page to the printer controller 98 , The printer controller 98 Controls after receiving the image information for a page from the CPU 97 the printer 99 in such a manner that the image information for one page is recorded.

The CPU 97 receives the image information for the next page in the course of recording by the printer 99 ,

The Images are received in the manner described above and recorded.

As described above According to the invention high quality Images without any fogging, a faulty cleaning and a reduction in transmission efficiency be trained, even during long-term operation, and also without decreasing the image density and without too any uneven pictures respectively, even in a low humidity environment.

EXAMPLES

The The present invention will be described below in more detail by way of illustration of Examples and Comparative Examples be written. Hereinafter "Part (s)" refers to "part (s) by weight" in each Occur.

example 1

In a four-necked flask equipped with a TK-homomixer type high-speed agitator, 710 parts of ion-exchanged water and 480 parts of 0.1 mol / liter Na ₃ PO ₄ aqueous solution were introduced, and the number of revolutions of the homomixer was set to 14,000 rpm to carry out the Mixed. The resulting mixture was heated to 63 ° C. Then, 62 parts of an aqueous 1.0 mol / liter of CaCl ₂ solution is added in small portions in a batch manner to prepare an aqueous medium containing fine particles of a poorly water-soluble dispersion stabilizer Ca ₃ (PO ₄ ) ₂ .

Meanwhile, a disperse phase system has been produced.

The above materials were dispersed for 3 hours by means of an agitating ball mill. Thereafter, to the obtained mixture, the following components were added, followed by further dispersion for 2 hours by means of the agitating ball mill, and thus the disperse phase system was prepared.

When next was the disperse phase system after the addition of 8 parts of a Polymerization Initiator 2,2'-Azo-bis (2,4-dimethylvaleronitrile) into the above watery Dispersion medium for carrying out a granulation for Introduced for 15 minutes at 14,000 rpm. Thereafter, the high-speed agitator was stirred with a stirrer Replaced propeller blades and the polymerization was over 5 hours at 50 rpm. Then its internal temperature was raised to 80 ° C and the polymerization became for further 5 hours. After the polymerization was completed, the generated slurry chilled and diluted hydrochloric acid became dissolution of the dispersant, further followed by a wash with water, a drying and a classification, to toner particles having a weight-average particle diameter of 7.0 μm.

Next, to 100 parts of the toner particles thus obtained were externally i) 0.9 parts of small particle diameter hydrophobic fine silica particles (silica A-1; BET specific surface area: 280 m ² / g; water wettability: 78%; triboelectricity amount: -98 mC / kg) obtained by surface-treating 100 parts of silica having a primary particle 50% particle diameter of about 7 nm with 14 parts of hexamethyldisilazane; ii) 0.4 part of large particle diameter hydrophobic fine silica particles (silica B-1; BET specific surface area) : 31 m ² / g; water wettability: 92%; triboelectricity: -83 mC / kg) obtained by surface-treating 100 parts of silicon oxide having a 50% particle diameter of the primary particles of about 50 nm with 12 parts of dimethylsilicone oil (50 cSt at 25 ° C) and iii) 0.3 parts of fine alumina particles (alumina C-1; BET specific surface area: 85 m ² / g; water wettability: 55%; electric quantity: -28 mC / kg) obtained by surface-treating 100 parts of alumina having a primary particle 50% particle diameter of about 15 nm with 10 parts of isobutyltrimethoxysilane, by means of a Henschel mixer FM10B to obtain a toner. The toner thus obtained had an average circularity of 0.971.

The resulting toner was prepared as a one-component developer ( 1 ) and was incorporated into a modified device of a commercially available CANON LBP-2030 laser beam printer which, as described in U.S. Pat 4 has been modified. Using this, evaluation was carried out by the method described below.

The modified device of the LBP-2030 is as in 4 shown constructed. Using a rotating unit 4 as a development device into which the development assembly 70 of in 1 The one-component nonmagnetic development system in which the one-component non-magnetic developer is used is detachably shown as a black development package, respectively 4bk , a yellow development board 4Y , a magenta development board 4M and a cyan developing assembly 4C The first thing that can be mounted on an intermediate transfer drum 5 transferred to corresponding color toners are formed a multi-toner image, secondly transferred once to a recording medium P and then fixed to the recording medium P by means of heat. His fuser assembly 3 is also modified to be constructed in the following manner.

As the fuser roller 3a the fixing assembly 3 For example, a roller is used which comprises an aluminum core shaft coated with two types of layers. In a lower layer thereof, high temperature vulcanized silicone rubber (HTV silicone rubber) is used as an elastic layer. The elastic layer is 2.1 mm thick and has a rubber hardness of 3 ° (JIS-A). In an upper layer, a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) formed in a thin film by spray coating is used as a releasing layer. The thin film is 20 μm thick.

The pressure roller 3b the fixing assembly 3 has, similar to the fuser roller 3a A structure in which a core shaft is coated with a lower layer of an elastic layer of silicone rubber and an upper layer of a fluorine resin release layer made of the same materials and with the same thickness and the same physical property values ,

The nip at the fixing zone is 9.5 mm; the fixing pressure to 2.00 × 10 ⁵ Pa; and the fuser roller surface temperature is set to 180 ° C in the standby mode. The fixing oil coating mechanism is degraded.

As the intermediate transfer drum 5 For example, a drum is used which comprises an aluminum cylinder whose surface is covered or coated with an elastic layer formed of a mixture of NBR and epichlorohydrin in a thickness of 5 mm.

The cyan development board 4C of the above-modified device of the LBP-2030 was charged with 160 g of the above non-magnetic one-component developer ( 1 ). As the recording medium P, commercially available copy sheets CLC Paper A4 (available from CANON SALES INC., Basis weight: 81.4 g / m ² ) were incorporated into the receiver 7 On and continuous operating tests were performed under the conditions shown below.

Primary charging conditions:

From an energy source (not shown) was attached to the charge roller 2 a charge bias voltage generated by superimposing a DC voltage of -600 V and an AC voltage of 1,150 Hz with sinusoidal wave in an amplitude of 2 kVpp to uniformly charge the photosensitive drum of insulating material while causing electric charges to migrate by discharge were.

Conditions for the latent Imaging:

The surface of the photosensitive drum 1 , which had been uniformly charged, was irradiated with laser light L to perform exposure to form electrostatic latent images. The intensity of the laser light was adjusted to provide a surface potential of -150 V in the exposed areas.

Development conditions:

To the development sleeve of the cyan development board 4C , in the 4 A development bias voltage, generated by superimposing a DC voltage of -350 V and an AC voltage of 2.250 Hz with sinusoidal wave in an amplitude of 1.8 kVpp, was generated to generate an alternating electric field at the gap between the developing sleeve and the photosensitive drum 1 at which the toner on the developing sleeve for flying on the photosensitive drum 1 was brought to carry out a development, created.

Primary transfer conditions:

On the photosensitive drum 1 toner image formed on the intermediate transfer roller 5 by means of the development module 4C was transferred to the aluminum drum 5a a DC voltage of +300 V is applied as the primary transfer bias voltage.

Secondary transmission conditions:

To put that first on the intermediate transfer drum 5 transferred toner image to the recording medium P as a second step, a DC voltage of +1.950 V to the transmission device 8th as the second or secondary transfer bias.

 evaluation

(1) image density

Each in an environment of 30 ° C / 80 % RH and 15 ° C / 5 % RF becomes a pattern with a frame percentage of 6% (A4) continuous printed. A black full pattern will be on the 50th sheet, 2,000. Sheet and 5,000. Sheet printed and the density of areas of 3 cm from the paper ends is measured (three-point mean in the middle and at both ends). The density is measured with a RD918 reflection densitometer (manufactured by Macbeth Co.).

(2) Uneven images

Each in an environment of 30 ° C / 80 % RH and 15 ° C / 5 % RF becomes a pattern with a frame percentage of 6% (A4) continuous printed. A black full pattern is continuously added to 10 sheets 50th sheet, 2,000. Sheet and 5,000. Sheet printed and the density on the surfaces 3 cm and 15 cm from the paper sheets of the 10th sheet are measured (Three-point mean in the middle and the two ends), and indeed through the Relexometer RD918. The density difference at these two Points is evaluated to evaluate uneven images.

(3) fog density

Each in an environment of 30 ° C / 80 % RH and 15 ° C / 5 % RF becomes a pattern with a frame percentage of 6% (A4) continuous printed. A pattern with a picture percentage of 2% will be continuous 50 leaves at the 50th sheet, 2,000. Sheet and 5,000. Sheet printed and afterwards becomes a white one Full color pattern printed on a sheet. The reflection of this Print and that of a virginal Papiers are measured and the difference between them is called Veil density viewed.

The results of the evaluation are shown in Table 1. Example 2

The The above materials were prepared using a Henschel mixer and the obtained mixture was dried by a twin screw extrusion kneader melt-kneaded. Thereafter, the obtained kneaded product was added Using a hammer mill comminuted and the comminuted product was powdered by means of a jet mill, followed by classification to toner particles with a weight average Particle diameter of 8.8 μm to obtain.

Next, to 100 parts of the toner particles thus obtained, i) 1.2 parts of small particle diameter hydrophobic silica fine particles (silica A-2; BET specific surface area: 125 m ² / g; water wettability: 93%; triboelectricity: -115 mC / kg) obtained by surface-treating 100 parts of silica having a primary particle 50% particle diameter of about 12 nm with 11 parts of isobutyltrimethoxysilane, ii) 0.5 part of large particle diameter hydrophobic fine silica particles (silica B-2; BET specific surface area: 75 m ² / g; water wettability: 90%, triboelectricity amount: -95 mC / kg) obtained by surface treatment of 100 parts of silica having a primary particle 50% particle diameter of about 30 nm with 15 parts of dimethylsilicone oil (50 cSt at 25 ° C and iii) 0.5 part of fine alumina particles (alumina C-2; BET specific surface area: 60 m ² / g; water wettability: 70%; tribo dielectric quantity: -17 mC / kg) obtained by surface-treating 100 parts of alumina having a primary particle 50% particle diameter of about 20 nm with 15 parts of isobutyltrimethoxysilane externally by means of a Henschel mixer FM10B to obtain a toner. The toner thus obtained had an average circularity of 0.938. The obtained toner was evaluated in the same manner as in Example 1.

The results of the evaluation are shown in Table 1. Example 3

The The above materials were prepared using a Henschel mixer and the obtained mixture was dried by a twin screw extrusion kneader melt-kneaded. Thereafter, the obtained kneaded product was added Using a hammer mill crushed and the minced product was criptron (manufactured by Kawasaki Heavy Industries, Ltd.), finely pulverized, followed by classification to toner particles with a weight average Particle diameter of 6.0 microns too receive.

Next, to 100 parts of the thus obtained toner particles were i) 1.3 parts of small particle diameter hydrophobic fine silica particles (silica A-3; BET specific surface area: 160 m ² / g; water wettability: 82%; triboelectricity amount: -107 mC / kg) obtained by surface treatment of silica having a primary particle 50% particle diameter of about 10 nm with 13 parts of hexamethyldisilazane; ii) 0.4 part of large particle diameter hydrophobic fine silica particles (silica B-3; BET specific surface area: 55 m ² / g; water wettability: 88%; triboelectricity amount: -98 mC / kg) obtainable by surface treatment of 100 parts of silica having a primary particle 50% particle diameter of about 40 nm with 13 parts of dimethylsilicone oil (50 cSt at 25 ° C) and iii) 0.1 part of fine alumina particles (alumina C-3; BET specific surface area: 100 m ² / g; water wettability: 21%; triboelectr amount: -5.3 mC / kg) externally by means of a Henschel mixer FM10B to obtain a toner. The toner thus obtained had a circularity of 0.946. The obtained toner was evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Examples 4 to 6

magenta Toner particles having a weight average particle diameter of 6.5 μm, yellow toner particles having a weight average particle diameter of 7.2 μm and black toner particles having a weight-average particle diameter of 5.5 μm were obtained in the same manner as in Example 1, except the C.I. Pigment Blue 15: 3 which had been used therein by 14 parts of C.I. Pigment Red 122, 10 parts of C.I. Pigment Yellow Replaced 17 or 12 parts of carbon black has been.

Next, to 100 parts of each color toner particle thus obtained, i) 1.0 part of silica A-3 used in Example 1, ii) 0.2 part of large particle diameter hydrophobic fine silica particles (silica B-4; Surface: 43 m ² / g; water wettability: 85%; triboelectricity amount: -71 mC / kg) obtainable by surface treatment of 100 parts of silica having a primary particle 50% particle diameter of about 45 nm with 10 parts of dimethylsilicone oil (50 cSt at 25 ° C) and iii) 0.08 part of fine alumina particles (alumina C-4, BET specific surface area: 145 m ² / g, water wettability: 10%, triboelectricity amount: -7.8 mC / kg), externally by Henschel Mischers FM10B added to obtain a magenta toner (Example 4), a yellow toner (Example 5) and a black toner (Example 6). The resulting toners had an average circularity of 0.978, 0.962, and 0.983 with respect to the magenta toner, the yellow toner, and the black toner, respectively. The thus obtained toners were evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Example 7

One Toner was obtained in the same manner as in Example 1, except that used in Example 1 alumina C-1 by 0.3 parts of the alumina C-4 used in Examples 4 to 6 replaced has been. The obtained toner was prepared in the same manner as evaluated in Example 1.

The Results of the evaluation are shown in Table 1.

Example 8

The Toner particles used in Example 2 became spherical Treatment over 2 hours under the conditions of a treatment temperature of 55 ° C and a stirring blade peripheral speed of 50 m / s using a hybridizer (manufactured by Nara Kikai Seisakusho) subjected to toner particles with a weight average Particle diameter of 8.6 microns to obtain.

To The toner particles thus obtained were externally silicon oxide A-2, the silica B-2 and the alumina C-2 in the same manner as in Example 2 to obtain a toner. The thus obtained Toner had an average circularity of 0.955. The obtained Toner was evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 1

To 100 parts of the toner particles used in Example 1 were i) 1.3 parts of hydrophobic fine silica particles having a primary particle diameter of about 50% particle diameter (R974; available from Nippon Aerosil Co., Ltd., treated with dimethyldichlorosilane; Surface area: 183 m ² / g; water wettability: 43%; triboelectricity amount: -73 mC / kg), ii) 0.4 part of hydrophobic fine silica particles having a primary particle 50% particle diameter of about 16 nm (R972, available from Nippon Aerosil Co., Ltd .; treated with dimethyldichlorosilane; BET specific surface area: 115 m ² / g; water wettability: 45%; triboelectricity amount: -65 mC / kg) and iii) 0.1 part of hydrophobic fine alumina particles having a 50% Particle diameter of the primary particles of about 15 nm (RFY-C, available from Nippon Aerosil Co., Ltd., BET specific surface area: 80 m ² / g, water wettability: 34%, triboelectricity amount: -12 mC / kg), external by means of a Henschel mixer FM10B to obtain a toner. The toner thus obtained had an average circularity of 0.971. The obtained toner was evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 2

To 100 parts of the toner particles used in Example 1 were 1.1 Parts and 0.5 parts of silica A-1 and silicon oxide B-1, respectively, used in Example 1, externally without using the Aluminum oxide C-1 added by means of a Henschel mixer FM10B, to get a toner. The toner thus obtained had a middle one circularity from 0.971. The obtained toner was processed in the same manner evaluated as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 3

A toner was obtained in the same manner as in Example 3 except that to 100 parts of the toner particles used therein were 0.2 part of fine alumina particles (alumina C-5; BET specific surface area: 230 m ² / g; water wettability: 5 Triboelectricity quantity: -33 mC / kg) were added instead of the aluminum oxide C-3. The toner thus obtained had an average circularity of 0.946. The obtained toner was evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 4

A toner was obtained in the same manner as in Comparative Example 1 except that the hydrophobic silica R-972 used therein was mixed with 0.4 part of hydrophobic fine silica particles (silica B-5; BET specific surface area: 95 m ² / g; water wettability: 65%; triboelectricity: -92 mC / kg) obtained by surface-treating 100 parts of silicon oxide having a 50% particle diameter of the primary particles of about 19 nm with 8 parts of dimethylsilicone oil (50 cSt at 25 ° C), have been replaced. The toner thus obtained had an average circularity of 0.971. The obtained toner was evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 5

To 100 parts of the toner particles used in Example 1 became 0.9 Parts and 0.7 part of silica B-1 and alumina C-1, respectively used in Example 1, externally without using the Silicon oxide A-1 added by means of a Henschel mixer FM10B, to get a toner. The toner thus obtained had a middle one circularity from 0.971. The obtained toner was processed in the same manner evaluated as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 6

To 100 parts of the toner particles used in Example 1 were 1.2 Parts and 0.4 part of the silica A-1 or alumina C-1, used in Example 1, externally without using the Silicon oxide B-1 added by means of a Henschel mixer FM10B, to get a toner. The toner thus obtained had a middle one circularity from 0.971. The obtained toner was processed in the same manner evaluated as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 7

A toner was obtained in the same manner as in Example 3 except that the silica B-3 used therein was charged with 0.4 part of hydrophobic fine silica particles (silica B-6; BET specific surface area: 13 m ² water wettability: 63%, triboelectricity amount: -48 mC / kg), obtainable by surface treatment of 100 parts of silica having a primary particle 50% particle diameter of about 160 nm with 5 parts of dimethylsilicone oil (50 cSt at 25 ° C.) has been. The toner thus obtained had an average circularity of 0.946. The obtained toner was evaluated in the same manner as in Example 1.

The Results of the evaluation are shown in Table 1.

Comparative Example 8

A toner was obtained in the same manner as in Example 3 except that the silica A-3 used therein was mixed with 1.3 parts of hydrophobic fine silica particles (silica A-4; BET specific surface area: 86 m ² water wettability: 75%, triboelectricity amount: -70 mC / kg) obtainable by surface treatment of 100 parts of silica having a primary particle 50% particle diameter of about 23 nm with 7 parts of hexamethyldisilazane. The toner thus obtained had an average circularity of 0.946. The obtained toner was evaluated in the same manner as in Example 1. The results of the evaluation are shown in Table 1.

Example 9

160 g each of the cyan toner produced in Example 1, the magenta toner produced in Example 4, the yellow toner produced in Example 5 and the black toner used in Example 6 were wt into the cyan development board 4C , the magenta development board 4M , the Yellow Development Board 4Y and the black development board 4bk , preferably the modified machine of LBP-2030 used in Example 1, in which the developing assembly 70 of the non-magnetic one-component development system disclosed in U.S. Pat 1 shown as removable from the black development package respectively 4bk , the Yellow Development Board 4Y , the magenta development board 4M and the cyan development board 4C are mounted. As the recording paper P, commercially available CLC paper-A4 was incorporated in the recording 7 filled in and full color images were created. As a result, sharp images having a sufficiently high image density and excellent gradation without any erroneous transfer, fogging, defective cleaning and no toner dots around the line images were obtained.

Claims (34)

A toner comprising toner particles and an external additive, wherein: the toner particles have a weight average particle diameter of 4 μm to 9 μm; and the external additive (i) first hydrophobic fine silica particles having a small particle diameter (A) having a BET specific surface area of 100 m ² / g to 350 m ² / g and a primary particle 50% particle diameter of 5 nm to 20 nm which have been treated with a silane, (ii) second hydrophobic silica fine particles having a large particle diameter (B) having a BET specific surface area of 15 m ² / g to 80 m ² / g and a primary particle 50% particle diameter of 30 nm to 150 nm, which have been treated with a silicone oil, and (iii) fine alumina particles (C) having a BET specific surface area of from 50 m ² / g to 150 m ² / g. The toner according to claim 1, wherein said small particle diameter hydrophobic fine silica particles (A) have a BET specific surface area of from 150 m ² / g to 300 m ² / g. The toner according to claim 1, wherein the hydrophobic silica fine particles with small Particle diameter (A) a Triboelektrizitätsmenge of -40 mC / kg to -150 mC / kg. The toner according to claim 1, wherein the treatment of the hydrophobic fine silica particles with small particle diameter (A) silane used a treatment agent is, selected from that of an alkoxysilane, a silazane and a chlorosilane existing group. The toner according to claim 1, wherein the treatment of the hydrophobic fine silica particles with small particle diameter (A) silane used a disilazane is. The toner according to claim 1, wherein the hydrophobic silica fine particles with small Particle diameter (A) with the silane in an amount of 5 parts by weight to 25 parts by weight, based on 100 parts by weight of the fine Silica particles have been treated. The toner according to claim 1, wherein the hydrophobic silica fine particles with small Particle diameter (A) have a water wettability of 70% or more. The toner according to claim 1, wherein said large particle diameter hydrophobic silica fine particles (B) have a BET specific surface area of from 20 m ² / g to 60 m ² / g. The toner according to claim 1, wherein the hydrophobic silica fine particles having a large particle diameter (B) a quantity of triboelectricity from -60 mC / kg to -100 mC / kg. The toner according to claim 1, wherein the treatment of the hydrophobic fine silica particles with great Particle diameter (B) used silicone oil is a treatment agent, that made of dimethylsilicone oil, methylphenyl and methyl hydrogen silicone oil existing group selected is. The toner according to claim 1, wherein the silicone oil used for treating the hydrophobic silica fine particles having a large particle diameter (B) has a viscosity of 1.0 cm ² / s or less (100 cSt or less) at 25 ° C. The toner according to claim 1, wherein the hydrophobic silica fine particles having a large particle diameter (B) with the silicone oil in an amount of 2 parts by weight to 20 parts by weight, based to 100 parts by weight of the fine silica particles have been. The toner according to claim 1, wherein the hydrophobic silica fine particles having a large particle diameter (B) have a water wettability of 80% or more. The toner according to claim 1, wherein the fine alumina particles (C) have a triboelectricity amount of +30 mC / kg to -20 mC / kg. The toner according to claim 1, wherein the fine alumina particles (C) have a water wettability of 30% or less. The toner according to claim 1, wherein the hydrophobic silica fine particles with small Particle diameter (A) to the toner in an amount (a) of 0.3 Parts by weight up to 2.5 parts by weight, based on 100 parts by weight the toner particles have been added, the hydrophobic fine Silica particles with large Particle diameter (B) to the toner in an amount (b) of 0.05 Parts by weight up to 1.5 parts by weight, based on 100 parts by weight the toner particles, and the fine alumina particles (C) to the toner in an amount (c) of 0.01 parts by weight 2.0 parts by weight based on 100 parts by weight of the toner particles have been added. The toner according to claim 16, wherein the hydrophobic silica fine particles with small Particle diameter (A), the hydrophobic fine silica particles with big Particle diameter (B) and the fine alumina particles (C) in an amount (a), amount (b) and amount (c) in the following, respectively Fulfilling relationship relationship have been added: a: b: c = 1: 0, 10 - 0, 65 : 0, 05 - 0, 50th The toner according to claim 1, wherein the fine alumina particles (C) have a water wettability of greater than 30% and the hydrophobic silica fine particles small particle diameter (A) to the toner in an amount (a) from 0.3 parts by weight to 2.5 parts by weight based on 100 parts by weight of the toner particles have been added the hydrophobic silica fine particles having a large particle diameter (B) to the toner in an amount (b) of 0.05 parts by weight to 1.5 parts by weight, based on 100 parts by weight of the toner particles, and the fine alumina particles (C) with a water wettability of more than 30% to the toner in an amount (c1) of 0.05 parts by weight to 2.0 parts by weight, based on 100 parts by weight of the toner particles are. The toner according to claim 18, wherein the hydrophobic silica fine particles with small Particle diameter (A), the hydrophobic fine silica particles with big Particle diameter (B) and the fine alumina particles (C) having a water wettability of more than 30% in an amount (a), amount (b) or quantity (c1) satisfying the following relationship relationship have been added. a: b: c1 = 1: 0, 10 - 0.65: 0, 20 - 0, 50th The toner according to claim 1, wherein the fine alumina particles (C) have a water wettability of not more than 30% and the hydrophobic fine silica particles small particle diameter (A) to the toner in an amount (a) from 0.3 parts by weight to 2.5 parts by weight based on 100 parts by weight of the toner particles have been added the hydrophobic silica fine particles having a large particle diameter (B) to the toner in an amount (b) of 0.05 parts by weight to 1.5 parts by weight, based on 100 parts by weight of the toner particles, were added and the fine alumina particles with a water wettability of not more than 30% to the toner in an amount (c2) of 0.01 part by weight to 1.0 part by weight, based on 100 parts by weight of the toner particles have been. The toner according to claim 20, wherein the hydrophobic silica fine particles with small Particle diameter (A), the hydrophobic fine silica particles with big Particle diameter (B) and the fine alumina particles (C) having a water wettability of not more than 30% in an amount (a), Quantity (b) or quantity (c2) satisfying the following relationship relationship have been added: a: b: c2 = 1: 0, 10 - 0, 65 : 0, 05 - 0, 35th The toner according to claim 1, wherein the toner particles have a weight-average particle diameter of 4 μm up to 9 μm exhibit. The toner according to claim 1, which has an average circularity of 0.950 to 1.000. The toner according to claim 1, which has an average circularity of 0.950 to 0.990. The toner according to claim 1, which has an average circularity of 0.960 to 0.985. The toner according to claim 1, wherein the toner particles are toner particles formed by a suspension polymerization process in which a polymerizable monomer composition in an aqueous Medium has been polymerized. The toner according to claim 1, wherein the toner particles are toner particles, which by a mechanical Pulverization process has been created with the following steps are: melt-kneading a toner material with a binder resin and mechanically pulverizing the resulting kneaded product. The toner according to claim 1, wherein the toner particles are subjected to a spherical treatment have been. The toner according to claim 1, which is obtained by mixing the toner particles, the hydrophobic fine silica particles with small particle diameter (A), of the hydrophobic fine silica particles with big Particle diameter (B) and fine alumina particle (C) has been produced by means of a mixing machine. An image forming method, comprising the following Steps: a generating step for an electrostatic latent Image for generating an electrostatic latent image on a a latent image bearing element; and a development step to the development of the element bearing a latent image generated electrostatic latent image with a toner; in which in the development step of the toner on a developer-carrying member by means of a brought into contact with the developer carrier element developer feeder supplied is, the layer thickness of the toner by means of a with the surface of the Developer carrying member in touch adjusted developer layer thickness regulating element is regulated and the electrostatic latent image with the toner on the The developer carrying member supported, Layer thickness-regulated toner layer is developed; thereby marked that the toner is a toner according to any one of of the preceding claims is. Use of a toner according to any one of claims 1 to 29 in a device unit ( 70 ) detachably mountable to the main assembly of an image forming apparatus; the unit comprising the following: a developer container ( 71 ) for holding the toner; a developer carrier element ( 72 ) for supporting the toner held in the developer container and for transporting the toner to a development zone. Use according to claim 31, wherein the device unit ( 70 ) further comprising the following: (i) a developer supply roller (in contact with the developer carrier element surface) ( 73 ) for supplying the toner to the surface of the developer-carrying member ( 72 ) and (ii) a developer layer thickness regulating element ( 74 ) for regulating the layer thickness of the on the developer carrier element ( 72 ) generated toner in the form of an elastic blade. A device unit ( 70 ) detachably mountable to the main assembly of an image forming apparatus; the unit comprising: a toner ( 76 ) according to any one of claims 1 to 29; a developer container ( 71 ) for holding the toner; and a developer carrier element ( 72 ) for carrying the toner held in the developer container and for transporting the toner ( 76 ) to a development zone. The device unit ( 70 ) according to claim 33, further comprising: (i) a developer (in contact with the developer carrier member surface); 73 ) for supplying the toner ( 76 ) to the surface of the developer carrier element ( 72 ) and (ii) a developer layer thickness regulating element ( 74 ) for regulating the layer thickness of the on the developer carrier element ( 72 ) generated toner ( 76 ) in the form of an elastic blade.